What kind of nuts are gluten free?

All nuts. All nuts are gluten-free. Gluten is a protein found in wheat, barley and rye. These are cereal grains.
Nuts are gluten-free. Nuts are naturally gluten-free, but processed nuts (such as candy-coated nuts) may have picked up some gluten from wheat, barley, malt, or rye ingredients during the processing. One should always check the labels on processed nuts to see if they say "gluten-free".